The present invention relates to a spool for a correction tape assembly. More particularly, it relates to a spool adapted to be used in a winding side of a correction tape assembly which can be used one or more time (hereinafter referred to as a spool for reversible-type correction tape assembly).
Generally, a correction tape for a typewriter will have ink stuck to its lift-off surface only once, and it will be considered to be no longer suitable for further use. Therefore, a conventional correction tape assembly is designed in a suitable structure for only one use. For example, such a type of correction tape assembly includes a dispensing core to be set onto a dispensing mechanism of a typewriter, a correction tape having an end which is fixed to the dispensing core and is wound around the dispensing core, and a spool onto which the free end of the correction tape is fixed. The used portion of the correction tape is wound around the spool which is set onto a winding mechanism of the typewriter.
However, it was recently found that such correction tapes can be used several times, and therefore, a reversible-type correction tape assembly has been proposed to enable re-use of the correction tape without change of the construction of conventional typewriters. For example, U.S. Pat. No. 4,518,128 discloses a reversible-type correction tape assembly comprising a correction tape; a dispensing core; a winding core which has the same shape and size as the dispensing core; a spool shaft capable of holding the winding core so that the winding core is not rotatable around the spool shaft and is slidable in the axial direction; and a cap detachably mounted to the top portion of the spool shaft for preventing slip-out of the winding core.
In the above-mentioned reversible-type correction tape assembly, the spool shaft and the cap may have screw means capable of engaging with each other, and the cap may be detachably fastened onto the top portion of the spool shaft by the screw means. Therefore, the two cores are exchangeable to each other, in order to remove the wound correction tape with the winding core from the winding mechanism and to re-set it on the dispensing mechanism of the typewriter.
However, in the above screw means, there is a disadvantage that the cap can automatically loosen and come off of the spool shaft when the correction tape is moved up in order to shift from an original lower position to an upper typing position, and as a result, the winding core slips out of the spool shaft.
The present invention is directed to eliminate the above disadvantage in the above-mentioned spool of the reversible-type correction tape assembly.
The main object of the present invention is to provide a spool for a reversible-type correction tape assembly, in which the cap is securely fastened onto the top portion of the spool shaft, but can be easily detached from the top portion of the spool shaft.
These and other objects of the present invention will become apparent from the description hereinafter).